Reversed stereoselectivity in iodohydroxylation of allenyl sulfides. An efficient synthesis of (Z)-3-organosulfur-2-iodo-2-propenols

Article abstract of DOI:10.1021/ol034109y

(Matrix presented) It is observed that the iodohydroxylation of 1, 2-allenyl sulfides with I₂ and water in aqueous acetone showed Z-selectivity, which is opposite to that of the iodohydroxylation of 1, 2-allenyl sulfoxides.

Full text of DOI:10.1021/ol034109y

ORGANIC
LETTERS
2
003
Vol. 5, No. 8
217-1219
Reversed Stereoselectivity in
Iodohydroxylation of Allenyl Sulfides.
An Efficient Synthesis of
1
(Z)-3-Organosulfur-2-iodo-2-propenols
Shengming Ma,*,‡,§ Xueshi Hao, and Xian Huang‡
‡
Department of Chemistry, Zhejiang UniVersity, Hangzhou 310027, P. R. China, and
State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic
Chemistry, Chinese Academy of Sciences, 354 Fenglin Lu,
Shanghai 200032, P. R. China
masm@pub.sioc.ac.cn
Received January 21, 2003
ABSTRACT
It is observed that the iodohydroxylation of 1,2-allenyl sulfides with I
2
and water in aqueous acetone showed Z-selectivity, which is opposite
to that of the iodohydroxylation of 1,2-allenyl sulfoxides.
Allenes show unique reactivities in organic synthesis due to
bond are synthetically attractive since two functional groups
1
4
the presence of the cumulated CdC double bonds. Recently,
are introduced at the same time. However, reports on the
2
,3
5
much attention has been paid to their reactivities. On the
addition reaction of allenes are limited due to the difficulty
other hand, addition reactions of a carbon-carbon multiple
in controlling the regio- and stereoselectivity. Recently, we
observed that (1) the regioselectivity of hydrohalogenation
reaction of electron-deficient allenes leading to â,γ-unsatur-
ated functionalized alkenes is controlled by the electronic
*
To whom correspondence should be addressed. Fax: (+86)21-
6
4166128.
‡
§
Zhejiang University.
6
Shanghai Institute of Organic Chemistry.
1) (a) The Chemistry of Allenes; Landor, S. R., Ed.; Academic Press:
effect of the electron-withdrawing group and (2) the
(
iodohydroxylation reaction of 1,2-allenyl sulfoxides exhibits
New York, 1982; Vols. 1-3. (b) The Chemistry of Ketenes, Allenes and
Related Compounds; Patai, S., Ed.; Wiley: New York, 1980; Vols.1 and
7
excellent regio- and E-stereoselectivity. In this paper, we
2
. (c) Brandsma, L.; Verkruijsee, H. D. Synthesis of Acetylenes, Allenes
and Cumulenes; Elsevier: New York, 1980. (d) Bruneau, C.; Dixneuf, P.
H. Compr. Org. Funct. Group Transform. 1995, 1, 953. (e) Marshall, J. A.
Chem. ReV., 1996, 96, 31. (f) Schuster, H. F.; Coppola, G. M. Allene in
Organic Synthesis; Wiley: New York, 1984. (g) Taylor, D. R. Chem. ReV.
(4) (a) Nakhmanovich, A. S.; Komarova, T. N.; Lopyrev, V. A. Russ. J.
Org. Chem. 2000, 11, 1551. (b) Chemistry of Dienes & Polyenes; Rappoport,
Z., Ed.; John Wiley & Sons Ltd.: New York, 2000; Vol. 2, pp 545-663.
(c) Beletskaya, I.; Moberg, C. Chem. ReV. 1999, 12, 3435. (d) Organose-
lenium Chemistry; Back, T. G., Ed.; Oxford University Press: New York,
1999; pp 35-66. (e) Mascavage, L. M.; Dalton, D. R. Trends Org. Chem.
1993, 1, 303. (f) Chemistry of Double-Bonded Functional Groups; Patai,
S., Ed.; Wiley: New York, 1997; Vol. 3, pp 1135-1222. (g) Han, L.;
Tanaka, M. Chem. Commun. 1999, 5, 395.
1
967, 67, 317. (h) Aso, M.; Kanematsu, K. Trends in Org. Chem. 1995, 5,
1
57. (i) Zimmer, R. Synthesis 1993, 165.
(2) For recent reviews, see: (a) Zimmer, R.; Dinesh, C. U.; Nandanan,
E.; Khan, F. A. Chem. ReV. 2000, 100, 3067. (b) Hashmi, A. S. K. Angew.
Chem., Int. Ed. 2000, 39, 3590. (c) Lu, X.; Zhang, C.; Xu, Z. Acc. Chem.
Res. 2001, 34, 535.
(
3) For some of our recent work, see: (a) Ma, S.; Zhao, S. J. Am. Chem.
(5) (a) Weiss, H. M.; Touchette, K. M. J. Chem. Soc., Perkin Trans. 2
1998, 6, 1523. (b) Breuer, K.; Teles, J. H.; Demuth, D.; Hibst, H.; Schafer,
A.; Brode, S.; Domgorgen, H. Angew. Chem., Int. Ed. 1999, 39, 1401. (c)
Barbero, A.; Garcia, C.; Pulido, F. J. Tetrahedron Lett. 1999, 36, 6649. (d)
Yang, F.; Wu, M.; Cheng, C. J. Am. Chem. Soc. 2000, 122, 7122. (e) Grigg,
R.; MacLachlan, W.; Rasparini, M. Chem. Commun. 2000, 2241. (f)
Suginome, M.; Ohmori, Y.; Ito, Y. J. Organomet. Chem. 2000, 611, 403.
Soc. 2001, 123, 5578. (b) Ma, S.; Wu, S. Chem. Commun. 2001, 441. (c)
Ma, S.; Wu, S. Tetrahedron Lett. 2001, 42, 4075. (d) Ma, S.; Shi, Z.; Wu,
S. Tetrahydron: Asymmetry 2001, 12, 193. (e) Ma, S.; Shi, Z. Chem.
Commun. 2002, 540. (f) Ma, S.; Jiao, N.; Zhao, S. Hou, H. J. Org. Chem.
002, 67, 2837. (g) Ma, S.; Duan, D.; Wang, Y. J. Comb. Chem. 2002, 4,
39. (h) Ma, S.; Yu, Z. Angew. Chem., Int. Ed. 2002, 41, 1775.
2
2
1
0.1021/ol034109y CCC: $25.00 © 2003 American Chemical Society
Published on Web 03/27/2003

report our recent results of highly stereoselective iodohy-
droxylation of 1,2-allenyl sulfides.
best results in terms of the yield of Z-4a was obtained at
room temperature in acetone/H O (4:1) (entry 6, Table 1).
2
The starting sulfides used in this study were prepared via
the reduction of 1,2-allenyl sulfoxides, which are easily
available from the reaction of progarylic alcohols with PhSCl.
We started this research with the iodohydroxylation of
Some typical results of the Z-iodohydroxylation of 1,2-
allenyl sulfides are summarized in Table 2. It is obvious that
3
-benzyl-1,2-butadienyl phenyl sulfide (1a) with I
2
2
and H O.
Table 2. Iodohydroxylation of 1,2-Allenyl Sulfides
Some typical results are summarized in Table 1. When we
Table 1. Iodohydroxylation of 1,2-Butadienyl Phenyl Sulfide
(1a)
1
entry
R1
R2
time (h) yield of 4a (%) Z/E
1
2
3
4
5
6
7
8
9
H
H
H
H
H
CH3
CH3
CH3
CH3
CH3 (1b)
i-Pr (1c)
n-C4H9 (1d )
n-C7H15 (1e)
Bn (1f)
CH3 (1g)
C2H5 (1h )
i-Bu(1i)
9
10
13.5
9.5
9.5
10.5
10
12
9
61 (4b)
56 (4c)
74 (4d )b
67 (4e)c
65 (4f)d
63 (4g)
94 (4h )
53 (4i)e
85 (4j)
72 (4k )
93 (4l)
80 (4m )
97/3
96/4
98/2
96/4
96/4
94/6
94/6
99/1
97/3
98/2
95/5
97/3
yield of
time
T
yield of
2a (E/Z)a
(Z)-4a (%)
(Z/E)a
entry
solvent
(h) (°C)
1
2
3
4b
5
6
7
CH3CN/H2O ) 4:1 16
CH3CN/H2O ) 4:1 16
acetone/H2O ) 2:1 10
acetone/H2O ) 2:1 10
acetone/H2O ) 4:1 11
acetone/H2O ) 4:1 13
15 30 (1.08:1)
28 16 (0.32/1)
0
0
0
t-C4H9 (1j)
C2H5 (1k )
n-C4H9(1l)
8 (1.07/1)
50 (>99:1)
1
1
1
0
1
2
C2H5
n-C4H9
n-C5H11 n-C5H11(1m )
8
10
10
0
22 (1.28/1)c 62 (>99:1)
15 16 (1.40/1)c 66 (>99:1)
28 16 (1.09/1) 68 (>99:1)
a
Unless otherwise stated, the corresponding aldehyde 2 was isolated in
acetone/H2O ) 2:1 10.5 15 12 (1.07/1) 66 (>99:1)
b
c
d
a trace amount. 14% of 2d was isolated. 18% of 2e was isolated. 18%
a
1
of 2f was isolated. e 14% of 2i was isolated.
Isolated yield with the Z/E ratio determined by H NMR spectra unless
otherwise stated. 4 equiv of I2 was used. The ratio was determined by
isolation.
b
c
the yields are from moderate to high with an excellent
Z-selectivity, and both 3-mono- and 3,3-disubstituted allenyl
performed the iodohydroxylation under the same reaction
conditions for 1,2-allenyl sulfoxides, only a Z/E mixture of
2
sulfides reacted smoothly with I in aqueous acetone. The
stereoselectivity of this reaction was determined by the NOE
7
2
1
-iodo-2-propenal 2a was obtained (entries 1 and 2, Table
). The configuration of the CdC bond in 2a was determined
experiment of (Z)-4d and the oxidation of (Z)-4d with
2 2 2 2
m-CPBA in CH Cl or H O in HOAc to the corresponding
7
by the NOE study. This product must be formed via the 2,1-
sulfoxide (Z)-5d (Scheme 2). It is obvious that the stereo-
iodohydroxylation intermediate 3a (path a, Scheme 1).
Scheme 2
Scheme 1
selectivity is completely opposite to the results for the
7
corresponding sulfoxides.
(
6) (a) Ma, S.; Shi, Z.; Li, L. J. Org. Chem. 1998, 63, 4522. (b) Ma, S.;
However, it is interesting to observe that when the reaction
was carried out in aqueous acetone the regioselectivity was
reversed to a fairly high extent leading to the formation of
synthetically useful 2,3-iodohydroxylation product Z-4a in
Wei, Q. J. Org. Chem. 1999, 64, 1026. (c) Ma, S.; Li, L.; Xie, H. J. Org.
Chem. 1999, 64, 5325. (d) Ma, S.; Wei, Q. Eur. J. Org. Chem. 2000, 1939.
(e) Ma, S.; Li, L. Synlett 2001, 1206. (f) Ma, S.; Li, L.; Wei, Q.; Xie, H.;
Wang, G.; Shi, Z.; Zhang, J. Pure Appl. Chem. 2000, 72, 1739. (g) Ma, S.;
Xie, H.; Wang, G.; Zhang, J.; Shi, Z. Synthesis 2001, 713. (h) Ma, S.; Yin,
S.; Li, L.; Tao, F. Org. Lett. 2002, 4, 505.
50% together with a 8% yield of 2a (entry 3, Table 1). The
1218
Org. Lett., Vol. 5, No. 8, 2003

When we used 1n as the starting allenyl sulfide, (Z)-1-
1′-cyclohexenyl)-1-iodo-2-(phenylsulfanyl)ethene 6n was
obtained via the dehydration of the iodohydroxylation
(
Scheme 4
product (Z)-4n (Scheme 3).
Scheme 3
atom. The regioselectivity in these reactions may be con-
trolled by the steric and electronic effects of substituents at
the two terminals of allenes. Although the real nature
controlling the stereoselectivity needs further attention, this
reaction provides an efficient route to the Z-isomer of
It can be assumed that the lone electron pair of sulfur atom
8
would interact with I
2
to form a molecular complex.
3
-organosulfur-2-iodo-2-propenols and may open up a new
Intramolecular electrophilic delivery of I
2
to the CdC bond
area for the control of selectivity in addition reactions of
allenes. The scope of this reaction, the real nature of the
Z-stereoselectivity, and the synthetic application of these
reactions are currently being carried out in our laboratory.
remote from the S group would form intermediate (Z)-7.
Upon hydrolysis, the reaction affords (Z)-4. The regioselec-
tivity may be attributed to the steric and electronic effect of
1
2
R , R , and thiophenyl in the starting allenyl sulfides. The
strong soft Lewis acid and base interaction between the
Acknowledgment. Financial support from the Major
State Basic Research Development Program (Grant No.
G2000077500), National Natural Science Foundation of
China, Cheung Kong Scholars Program, and Zhejiang
University are greatly appreciated. S.M. is the recipient of
9
positively charged iodine atom and S in (Z)-7 may be
responsible for the stereoselectivity of this reaction (Scheme
4
).
In conclusion, we have developed a highly regio- and
stereoselective addition reaction of 1,2-allenyl sulfides with
and H O. The Z-stereoselectivity for these reactions may
1
999 Qiu Shi Award for Young Scientific Workers issued
I
2
2
by Hong Kong Qiu Shi Foundation of Science and Technol-
ogy (1999-2003).
be explained by the soft Lewis base and acid interaction
between the sulfur atom and the positively charged iodine
Supporting Information Available: Typically experi-
mental procedure and analytical data for all products. This
material is available free of charge via the Internet at
http://pubs.acs.org.
(
7) Ma, S.; Wei, Q.; Wang, H. Org. Lett. 2000, 2, 3893.
(8) Lowry, T. H.; Richardson, K. S. Mechanism and Theory in Organic
Chemistry, 3rd ed.; Harper & Row Publishers: New York, 1987; p 319.
9) For intramolecular haloalkoxylation of 2-phenythio-2,3-allenols lead-
(
ing to 2,5-dihydrofurans, see: Yano, Y.; Ohshima, M.; Sutoh, S. J. Chem.
Soc., Chem. Commun. 1984, 695. Florio, S.; Ronzini, L.; Epifani, E.; Sgarra,
R. Tetrahedron 1993, 49, 10413.
OL034109Y
Org. Lett., Vol. 5, No. 8, 2003
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